Rabbi Yisrael Friedman was a popular early-19th-century chasidic leader in Ruzhin and then Sadigura. Though he left no writings, his teachings were collected and published after his death. One of these collections is titled Irin Kaddishin (Holy Angels). It contains chasidic insights on selected Torah portions, holidays, and other topics, including material from Rabbi Friedman’s son, Rabbi Avraham Yaakov Friedman, who succeeded his father and brother as rebbe in Sadigura.